A communications system includes a plurality of communications channels for transporting packets. The system also includes a gateway that is coupled to the communications channels. The gateway is configured to buffer a packet that is received over one of the communications channel from a first host in a queue and to determine a window value for maximizing transmission rate based upon occupancy of the queue. The gateway is configured to a second host according to a prescribed protocol to force use of the determined window value in the second host over another one of the communications channels. The present invention has particular applicability to an asymmetric bandwidth network, such as a two-way satellite system.